The present invention pertains to a device for the subsequent processing of printed products.
As used herein, “printed products” includes individual sheets or a collection of sheets or sections to be jointly processed by a transport device in order to modify the printed products. Known systems for the subsequent processing of printed products consist of a sequence of processing stations and usually feature several successive transport systems that transport the printed products to be processed to and from these processing stations. Revolving chains with corresponding transport element such as finger-shaped pushers or transport clamps are frequently used as transport systems, wherein each of the transport elements respectively accommodates a printed product such as, e.g., a printed sheet, a section, a book block or a partial block.
A common control is provided for coordinating the processes and motions of the transport systems and the processing stations in the required fashion. This control receives information from installed drives and sensors that serve for controlling and monitoring the respective systems and stations. Information on faulty processes or conditions received by the control is indicated with the aid of signal lamps that are spatially assigned to the respective processing stations. Furthermore, such processes and conditions, which are usually referred to as malfunctions, are visualized on the centralized or decentralized human-machine interface. This enables the operating personnel to detect and resolve the causative error.
It is also common practice to provide machine lighting systems that illuminate certain machine areas, particularly transport paths. These lighting systems enable the operating personnel to visually monitor the corresponding processes and therefore are usually arranged in the vicinity of inspection windows. These lighting systems are stationary and static and therefore not dependent on machine conditions and product conditions.
EP1952986A1 discloses a system for monitoring a device for processing printed products. The system is essentially formed by a lighting unit that can generate continuous light, as well as light flashes. In this case, the light flashes are synchronized with certain periodic motion sequences within the device for the subsequent processing of printed products such that these motions can be visually monitored by the operating personnel over a plurality of successive periods although the individual motion takes place too fast for the human eye.
This significantly simplifies the coordination of fast motions that are time-dependent on one another, particularly during the installation or set-up of the device. The strobe light also simplifies the analysis of processing errors in that recurring errors in very fast processes can be visually monitored during their development.
However, the thusly obtained information on the development of the error does not provide any useful reference to the current location of a faulty product. When the device stops after an error has occurred in order to enable the personnel to remove the faulty product, the location usually can only be roughly estimated, particularly at high transport speeds. The personnel is then forced to open the enclosure of the device at several locations until the faulty product is found. Several successive products have to be removed if the damage to the product caused by the malfunction cannot be directly detected visually.